The Group/Member and Related Objects window allows the construction of hierarchical structures of objects. A hierarchical structure is one which links items to one another in an ascending/descending classified arrangement of any number of levels.
Hierarchies have the following attributes:
oeach item can have only ONE parent (i.e. belong to ONE group)
oany group can have any number of subordinates (children)
In Vernon CMS there is no limit to the number of levels that you can have within an hierarchical structure. However, you do have to define these levels (types of groups) before you can use them. In Vernon CMS, there is only one hierarchical structure that any object can belong to. Therefore you need to be judicious and clear as to how you want to use this field before you start.
In general, you would use the group/member hierarchies where objects are naturally deemed to 'belong to' or form part of another object. In some instances this is obvious. For example, in archival cataloguing where there may be groups composed of series composed of items.
Other examples which are clearly candidates for this structure include:
oportfolios of artworks
oseries of artworks
When NOT to use the Group/Member facility
It is not usually appropriate to use the Group/Member facility for sets with multiple parts when those parts are not fully functional objects in their own right e.g. you would not use this facility when the photographs in an album could not, or should not, be removed from the album for independent display, study, loan, etc., or if the album itself was insignificant.
Nor would you use it for sets such as playing cards, Dinner sets, Silver services, etc. Objects of this nature are usually created as single objects with multiple parts. The Group/Member facility, instead, caters specifically for objects that can function individually, OR as part of a set (e.g., a single print from a portfolio of prints) i.e. for situations where a significant item is composed of other significant items.
It is also NOT necessary to use the Group/Member fields to associate objects which merely have the same attributes, e.g. the same donor, classification, department, materials, etc. These objects can already be easily retrieved and sorted based on these common attributes, and no additional grouping is required.
There is overlap between the group/member facility and the ability to include parts within a single object record.
PARTS:
Object Part and the associated Object Part Description field are used to identify parts of an object based on their potential for separate movement. That is, those parts which are currently separate, or could easily become separate, and which must be separately identified when recording details about the object's location.
The parts of a tea set might be the teapot, the teapot lid, 8 individual cups, 8 individual saucers, a sugar bowl, a sugar bowl lid, etc. The top and base of a salt shaker (currently screwed together but easily unscrewed) might be considered separate parts of the salt shaker, and you might also consider a chair and a broken-off arm of the chair to be separate parts of the chair (until they are eventually repaired).
When NOT to use parts
For example, where there are large groups of china that have varying marks, forms, sizes and condition but are all part of a 'set' (such as Wedgwood 'Asiatic Pheasant' pattern) then you could create a group for "Wedgwood 'Asiatic Pheasant'" pattern china and link all the items to this as members. You would not be able to use parts for these if they have been acquired at different times from different sources (as the acquisition information would have to be all merged into a single record without the precision of attribution at part level).
Another instance where you may choose NOT to use parts, is where the components are so significant that they each justify having their own record to ensure that data about each component is available discretely and separately. For example, if you were cataloguing the 78 pieces in the famous Lewis Chessmen, you would give each one a separate record linked to a group record which represents the set as a whole. But if you were cataloguing a chess set of lesser significance, you would probably use a single record, and then you could define the pieces as parts, if you wished.
For the 'Asiatic Pheasant' pattern Wedgwood china you could use the Decoration field (found in the Physical Aspects data entry window) to record this element of data. By doing this you could do a search for all objects which are made by Wedgwood AND have the 'Asiatic Pheasant' Decoration. This would preclude the need to create a group.
